Rockwell Automation 7000L PowerFlex Medium Voltage AC Drive (C Frame) - Classic Control - Manual (Page 283)

4-78 Commissioning
7000L-UM300I-EN-P – June 2013 7000 “C” Frame
Parameter "Autotune Lc" in "Autotuning" is set to the measured value
of commutation inductance, and parameter "Autotune select" is set to
Off. If the test is successful, parameter "L commutation" in "Current
Control" is set equal to "Autotune Lc". If the test fails, then parameter
"L commutation" is not changed and a warning is issued indicating the
cause of the failure:
L comm low - indicates that the measured commutation
inductance is less than 0.02 pu. The commutation inductance
must be tuned using the manual method described below.
L comm high - indicates that the measured commutation
inductance is greater than 0.15 pu. The commutation inductance
must be tuned using the manual method described below.
Commutation Inductance Manual Tuning (for 18P only)
1. Set parameter "Operating mode" in “Feature Select“ to DC
Current to enter dc current test mode.
Current Control Parameter Screen
2. Set parameter "Idc command test" in “Current Control” to 0.400 pu.
3. Set parameter "L commutation" in “Current Control” to an initial
value of 0.05 pu.
4. Connect an oscilloscope to the test points labeled VABI-OUT
and FAB1 on the SCBL board. Two sine waves of
approximately equal amplitude should be seen, with the
reconstructed line voltage FAB1 lagging the unfiltered voltage
VABI-OUT by 90 degrees. Adjust the triggering and time base
to display the positive half cycle of VABI-OUT with a scale of
20 degrees per major division.
5. Start the drive. The dc link current will rise to 0.4 pu.
Commutation notches will appear in the unfiltered line voltage
VABI-OUT as shown in the figure. Some distortion will appear
in the reconstructed voltage FAB1 around the zero crossings.